adlib.h

/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */
 
#ifndef AGOS_DRIVERS_ACCOLADE_ADLIB_H
#define AGOS_DRIVERS_ACCOLADE_ADLIB_H
 
#include "audio/adlib_ms.h"
 
namespace AGOS {
 
class MidiDriver_Accolade_AdLib : public MidiDriver_ADLIB_Multisource {
protected:
    static const byte RHYTHM_NOTE_INSTRUMENT_TYPES[40];
    static const uint16 OPL_NOTE_FREQUENCIES_INSTR_DAT[12];
    static const uint16 OPL_NOTE_FREQUENCIES_MUSIC_DRV[12];
 
public:
    MidiDriver_Accolade_AdLib(OPL::Config::OplType oplType, bool newVersion, int timerFrequency);
    ~MidiDriver_Accolade_AdLib() override;
 
    int open() override;
    using MidiDriver_ADLIB_Multisource::send;
    void send(int8 source, uint32 b) override;
    void deinitSource(uint8 source) override;
 
    // Read the specified data from INSTR.DAT or MUSIC.DRV.
    void readDriverData(byte *driverData, uint16 driverDataSize, bool isMusicDrv);
 
    // Returns the number of simultaneous SFX sources supported by the current
    // driver configuration.
    byte getNumberOfSfxSources();
    // Loads the specified instrument for the specified instrument source.
    void loadSfxInstrument(uint8 source, byte *instrumentData);
    // Sets the note (upper byte) and note fraction (lower byte; 1/256th notes)
    // for the specified SFX source.
    void setSfxNoteFraction(uint8 source, uint16 noteFraction);
    // Writes out the current frequency for the specified SFX source.
    void updateSfxNote(uint8 source);
    // Applies a workaround for an Elvira 1 OPL3 instrument issue.
    void patchE1Instruments();
    // Applies a workaround for a Waxworks OPL3 instrument issue.
    void patchWwInstruments();
 
protected:
    InstrumentInfo determineInstrument(uint8 channel, uint8 source, uint8 note) override;
 
    uint8 allocateOplChannel(uint8 channel, uint8 source, InstrumentInfo &instrumentInfo) override;
    uint16 calculateFrequency(uint8 channel, uint8 source, uint8 note) override;
    uint8 calculateUnscaledVolume(uint8 channel, uint8 source, uint8 velocity, const OplInstrumentDefinition &instrumentDef, uint8 operatorNum) override;
 
    void writePanning(uint8 oplChannel, OplInstrumentRhythmType rhythmType = RHYTHM_TYPE_UNDEFINED) override;
    void writeFrequency(uint8 oplChannel, OplInstrumentRhythmType rhythmType = RHYTHM_TYPE_UNDEFINED) override;
 
    // Copies the specified instrument data (in INSTR.DAT/MUSIC.DRV format)
    // into the specified instrument definition.
    void loadInstrumentData(OplInstrumentDefinition &definition, byte *instrumentData,
        OplInstrumentRhythmType rhythmType, byte rhythmNote, bool newVersion);
 
    // False if the driver should have the behavior of the Elvira 1 driver;
    // true if it should have the behavior of the Elvira 2 / Waxworks version.
    bool _newVersion;
 
    // from INSTR.DAT/MUSIC.DRV - volume adjustment per instrument
    int8 _volumeAdjustments[128];
    // from INSTR.DAT/MUSIC.DRV - simple mapping between MIDI channel and AdLib channel
    byte _channelRemapping[16];
    // from INSTR.DAT/MUSIC.DRV - simple mapping between MIDI instruments and AdLib instruments
    byte _instrumentRemapping[128];
    // Points to one of the OPL_NOTE_FREQUENCIES arrays, depending on the driver version
    const uint16 *_oplNoteFrequencies;
 
    // Data used by AdLib SFX (Elvira 2 / Waxworks)
 
    // Instrument definition for each SFX source
    OplInstrumentDefinition _sfxInstruments[4];
    // Current MIDI note fraction (1/256th notes) for each SFX source
    byte _sfxNoteFractions[4];
};
 
} // End of namespace AGOS
 
#endif